#include<stdio.h>
#include<stdlib.h>

int main()
{
	int i,j;
	int x=1;
	int y=20;
	int velocity=1;
	while(1)
	{
	    if(x>10 || x<1)
	    velocity=-1*velocity;
		x=x+velocity;
		system("cls");
	for(i=0;i<x;i++)
		printf("\n");
	for(j=0;j<y;j++)
		printf(" ");
	printf("o\n");
	}
	return 0;
}
